The 24 h oesophageal pH study is considered to be the gold standard for quantifying acid reflux.1 In this review we provide an evidence-based discussion of the role of 24 h pH studies as part of the investigation of children with suspected gastro-oesophageal reflux disease (GORD), and provide a practical guide on when a pH study is indicated, how to perform pH studies and how to interpret the results.

BACKGROUND

Gastro-oesophageal reflux (GOR) is defined as the effortless regurgitation of gastric contents into the oesophagus. GORD is defined as GOR associated with sequelae (table 1) including faltering growth.2

Physiological reflux is common in both primary and secondary care settings, and usually improves with age.3 Improvement is due to a combination of factors including growth in the length of the oesophagus, a more upright posture, increased tone of the lower oesophageal sphincter, and a more solid diet. In most cases, diagnosis is based on clinical assessment without the need for invasive testing. Investigation is reserved for those children in whom, for example, there is doubt about the diagnosis, or empirical therapy is considered to have failed, or for those children with extra-intestinal manifestations, such as acute life threatening events (ALTEs), apnoeas, Sandifer syndrome, asthma or faltering growth, in whom reflux is suspected to be a contributing factor.

In children with co-existing problems, such as asthma, cerebral palsy, epilepsy or congenital heart disease, GORD may be part of a complex interaction of pathologies as a primary or secondary phenomena. In such settings children may benefit from the diagnosis and treatment of GORD, and GORD may be improved by optimal treatment of the child’s co-existing problems.

Children with isolated GORD can remain symptomatic into adulthood; severe oesophagitis4 and oesophageal strictures from GORD in childhood have been reported.5

INVESTIGATION OF REFLUX

The investigation …